Multiple parachute arrangement



y 1936- E. L. HOFFMAN MULTIPLE PARACHUTE ARRANGEMENT Filed Jan. 10, 1933 INVENTOR WA RD we), STATES PATENT OFFICE,

MULTIPLE rAnAonUTE ARRANGEMENT e 7 Edward L. Hofiman, Daytonpohio i Application January 10, 1933, serial N6. s51,017

' 3 a 5 Claims. (01. 244- 21) 5 (Granted under the act of March a, 1883, as

- I amended April 30, 1928; 370 0. G. 757) The invention describedhereinmay be manufacturedandused. by orfor'the Government for governmental purposes, without the payment to ineofanyroyalty thereon e This invention relates to .quickopening para- .gchutes, and particularly to largesiz ed parachutes for'bringing entire aircraft orthe like safely to 'Th principal'object therefore of my invention is to provide a parachute mechanism that will open in a minimum amount of time and space, and when once in an open condition will be of suitable efiiciency. More specifically the object of this invention is to provide a parachute arrangement having a multiple of main canopies with the skirts of the canopies or their adjacent parts secured together.

A still further object of my invention is to provide a parachute of multiple canopies that is so constructed and arranged that the pilot parachutes of the same are highly effective.

A still further object of this invention is to provide a multiple canopied parachute that strings out after release and before opening similar to single canopied parachutes.

A still further object of my invention is to provide an efficient parachute of multiple canopies that is economical in manufacture and durable in use.

These and other objects will be apparent to those skilled in the art.

My invention consists in the construction, arrangement and combination of the various elements of the device, whereby the objects contemplated are attained as hereinafter more fully set forth, pointed out in my claims, all illustrated in the accompanying drawing, in which:

Fig. 1 is a side view of my parachute in an open condition for lowering an airplane or load safely to earth;

Fig. 2 is a side view of the upper portions of my device after release with both pilot parachutes open and just before the two main canopies start to open; and r Fig. 3 is a cross-sectional view of the adjacent portions of two parachute canopies showing one way of securing their skirt or marginal portions together. v

In experimenting with large parachutes for bringing down large loads, such as entire airplanes, I find that single canopied parachutes string out to undesirable lengths before opening. In the case of eighty-foot parachutes the pilot parachute strings out twelve feet, the main canopy strings out forty feet and the suspension lines string out sixty feet, making a grand total of one handred and twelve feet. In many instancesthis loss of valuable altitude is a serious matter and also requires an excessive period of time. To overcome such' disadvantages I employ a multiple of smaller'main canopies to replace the single large main canopy. By multiple, I have in mind V9 93 1. c e a d a h i the d w.- ing I illustrate only two main canopies, I' do not desire to limit myself to this number. Naturally when a plurality of canopies is used their diameter will be much less than the diameter of the single canopy they replace. This means that the number of feet the parachute mechanism strings out before opening will be greatly reduced, thereby saving both altitude and time of opening.

Tests of multiple canopied parachutes, however, show an undesirable substantial loss in efficiency over single canopies of similar effective areas. The chief reason for this is that each of the multiple canopies float at an angle of approximately ninety degrees to each other, or approximately at angles forty-five degrees to the vertical. This deploying of the canopies means that much valuable lift is lost due to the reduced projected efiective area of the parachute. To overcome a substantial amount of this loss I secure the skirts or adjacent parts of the canopies together, thereby preventing the spreading of the canopies from each other and holding them to float at a lesser angle to the horizontal with increased effective projected area.

Referring to the drawing I have used the numeral ID to designate the load object. The numerals l I and I2 designate the two main canopies of my parachute. The numeral I3 designates the suspension cords extending from the canopies H and 12 to the load object.

I have used the numeral [4 to designate a connecting member for linking the skirts or adjacent portions of the canopies together, as shown in Fig. 1. Any desirable securing means, however, may be used and in Fig. 3 I show the adjacent portions of the canopies stitched, sewed or otherwise secured together.

The numeral l5 designates a small pilot parachute secured to the upper portion of each of the canopies II and I2. In order that the two main canopies H and I2 will properly hold together and string out after release and before inflation similar to a single canopy, I connect their upper portions together by a frangible link member [6. As this member I6 is of low tensile strength it will break immediately upon the opening of the cano- V of my parachute without departing from the real; spirit and purpose of my invention and it isii'y" intention to cover by myiclaims'fany 'modified forms of structure, or use of mechanicalvequivalents which may be reasonably iii'cil'lideii scope. t u p U I claim:

1. In a parachute, a plurality of main canopies" having their adjacent marginal edges ii gedl y se- 1 cured together, a pilot parachuteseeured to the 7 top portion of each of said canopies, and

"pensiori cords' 'leadihg from said canopies;

"'ZF-Ina para hute; a multiple or main canopies s mmetr cal-1y and angularly disposed about "the axis offpull of 'a 'load object; having their adjacent s portion secured together," suspension lines to each of} saiwcanopies leading individually to sa d loa' c'al'wje'ct', a fra'ng'ible mean's 'for securing ia llfbree afil msa ifbr v c'entral'portions of'said canopies to one another; 1 j

a pilot parachute secured to the upper portion of one of said canopies. V

3. In a parachute, a multiple'of main canopies V symmetrically and angularly'disposed about the axis of pull of a load object, suspension cords lead- 5 ing individually from each of said canopies to said load objects, a frangible member for securing the upper portionsof said canopiesto each other, and aimlq araqhi e ed tam pper portion of each of 'said canopies. n 10 r '4. A parachute arrangement comprising, a plurality of main canopies symmetrically and angu- 1ar1yi 'dispb'sedabout the axis of pull of a load object, pilot, parachutes for opening said main parachutes; sensor suspension lines extending from 15 u eachioi'saidacanopieszto said load object and frangible means for securing the upper portions of said maincanbpies to one another. c I

51 In a parachute apparatus, a multiple of main said load pbjectj rionbieakable means ior'fixc'dly s ur ng e argina y portions 'offsidban- 25 opies tlally c lawns 1a pa l n ectin t h 111 ubt 

